China's top 10 scientific advances in 2020

5. Transparent ferroelectric single crystals with ultrahigh piezoelectricity

Transparent piezoelectrics are highly desirable for numerous hybrid ultrasound–optical devices ranging from photoacoustic imaging transducers to transparent actuators for haptic applications.

However, it is challenging to achieve high piezoelectricity and perfect transparency simultaneously because most high-performance piezoelectrics are ferroelectrics that contain high-density light-scattering domain walls.

The research team from Xi'an Jiaotong University led by professor Xu Zhuo demonstrated a method to enhance the performance of single crystal PMN-PT.

The research, published in the journal Nature, presents a paradigm for achieving high transparency and piezoelectricity by ferroelectric domain engineering, and the transparent ferroelectric crystals are expected to provide a route to a wide range of hybrid device applications, such as medical imaging, self-energy-harvesting touch screens and invisible robotic devices.